Since there are more than 60 offence types, just take a look at how many incidents happened for the first 10 offence type:

##                                                Aggravated Assault 
##                                0                             9862 
##                         Aircraft                            Arson 
##                                0                              105 
## Assembly or Gathering Violations                       Auto Theft 
##                             1076                             5757 
##              Auto Theft Recovery                       Ballistics 
##                             1277                             1273 
##                Biological Threat                        Bomb Hoax 
##                                3                              103

Take a look at how many incidents happened for each city:

##      Brighton   Charlestown    Dorchester      Downtown   East Boston 
##         25316          8150         54897         41994         16430 
##     Hyde Park Jamaica Plain      Mattapan       Roxbury  South Boston 
##         22416         22079         45966         62929         28602 
##     South End  West Roxbury 
##         50040         17147

City has the most incidents happened:

## [1] "Roxbury: 62929"

City has the least incidents happened:

## [1] "Charlestown: 8150"

Does the number of incidents varies significantly by cities?

Proportion

Generally speaking, there were some differences in the number of incidents happened between cities. Both plots shows that Roxbury and Dorchester have the largest number of incidents occurred during the past few years. Carlestown, Hyde Park and East Boston have relatively the least number of incidents occurred during the past few years. More generally, south part of Boston area tend to have more incidents happened than north part of Boston area.

Does the number of incidents varies significantly by years?

Proportion

Initially, I believe that there should be a difference in the number of accidents happened vary from years. However, from both plots above, there are no clear differences in number of incidents occurred between different years. There were relatively fewer incidents occurred in the year 2015 and the number of incidents tends to be similar from year 2016 till 2018. The number dropped a little bit this year in 2019.

The word most frequently appeared in incident description is property